Adhesive or cement and process for making the same



' Patented 1.51m

I aonimr monorwan-01m, momma anns'srvn on 01mm a m rnocass iron. mime 'rnasum No Drawing. Application nledfleptember 8, 1924, Serial No. 185,598, and in Great Britain leptember I The object of the present invention is to provide mediums of improved characteristics which can be used as adhesives or cements or in composltlons of a more or less r1g1d or 5 waterproof, or rigid andwaterproof nature,

such as amines, amides, hydrocarbons, and

aromatic oxy compounds which synthetic resins hereinafter shall be termed-condensation products. I have discovered that solutions of glutinous bodies commonly known as liquid glues such as is obtained by the action of diluted acetic or nitric acids on glue when heated or bydis'solving glue in a 20% calcium chloride solution, which liquid glues will not gelatinize or are rendered non-gelatinous do not precipitate with such condensa-.

tion products'altho'ugh for exampflz a solution of 'tannic acid will precipita all the lutin contained in such a solution. What is obtained is a viscous very tacky liquid of the consistency of treacle which may be diluted with water, alcohols, pyridine, aminessuch for example as aniline, or inorganic, aliphatic or aromatic acids 1' se or in solution.

. Alexander Bogue in his ook entitled Gelatin indicates on page 401 that gelatin which has been subjected to hydrolysis by the ac-' tion of high temperature, acids, alkalis, or

. otherwise, is converted, in proportion to the extent of such treatment, into a non-gelatinizing substance which no longer consists of protein gelatin, but of the cleavage products proteose and peptone. These have been called beta gelatin. Other authorities, for

' example Richard Kissling in his book entitled Leim und Gelatine, expresses the view that so called liquid lue consists partly of hydrolyzed glutin w ich is termed g elatose and partly of unconverted glutin. I believe that this so called beta gelatin or gelatose acts as a protective colloid between the condensation product and the protein gelatin and prevents precipitation thereof.

Experiments have further demonstrated thatin adding a solution of blood albumin or casein to -a mixture of such glue with the liquid or oil substance initially obtained when carbonyl compounds condense with organic substances such as aromatic oxy compounds, amines, amides or hydrocarbons no precipitation takes place although such roteids are coagulated if mixed simply wit substance.

In the belief that success would attend the use of other matters a series of tests over a wider range were made which showed that a the aforesaid discoveries were not restricted to the use of liquid glues, but that enerically the invention is to be regarded as t e employment, in combination wlth artificial resin solutlons and roteids or proteoids, of disperse systems an er which are included colloidal sols'or such oils as contain mucous substances in colloidal state or asphalts, resins, or other matter in ultra-microscopic dispersion, which oils are, according to more recent researches,

such oily considered as disperse phases which'will act as protective colloids and prevent a reaction of the artificial resins on the proteids or proteoids. The ex ression proteoid isintended to refer to a bumin bodies of the gelatine group in contradistinction to fibrin, albumin,

casein and the like, which will be hereinafter referred to by the expression proteids whereas proteoids may for the purpose of the present specification be'regarded as proteids of the gelatine group. (See Tlnele: Leim und Gelatine, second edition, page 2.)

Such disperse systems are for instance liquid glues, gum arabicsolution, dextrine solution, glycerinosols, glucose, vegetable glues such as pastes from starches, sea-weeds, agar-agar, etc., solutions of soaps, resinates, linoleates, india-rubber solutions, oil emulsions, that is emulsions of oil and water made by addition of emulsifying agents or emulsions of sulphonated oils and water. By soaps is tobe understood the alkaline saltsof known the higher fatty acids, while by resinates and hnoleates are to be understood the salts of resin and lineolic acids respectively, and by the expression oil emulsions is to be understood the emulsions prepared with oils and water byemeans of emulsifying agents or emulsions tween sulphonated oils and water. v

The artificial resin solutions may be first mixed or emulsified with the dis' rse systems and then added to the protei s or roteoids, or the disperse systems ma be rst .mixed with the proteids or proteoi s and the li uid artificial resins added afterwards.

n the carr g out of the first/discovery,

a soluble con ensation product which is soluble in the usual solvents, in contradistincti on to the'insoluble condensation products like bakelite B and C, may be used either per se or in suitable solvents. It is however more economical to use the thin oil which is formed at the beginning of the condensation between the phenols and the like and aldehydes ofwhic not only aliphatic but also aromatic .ones may be used or materials ca ableof evolving aldehydes. Such oily con ensation product ma be oured, while stirring vigorously, into liquid glue and the product thus obtained is exceedingly well suited for gluing ply woods or veneer under a pressure of say30O lbs. to square inch at a temperature of 110'-120 C. The gluing is efiected in from 8-10 minutes (if the laminae are about 1 mm. thick the glue beilnlgthereby rendered insolu le in water. owever neither such high ressure or temperature is necessary for: so idifying the glueor rendering it waterproof as it will obtain these qualities after some time if allowed to dry naturally between wood or if the laminae are treated on the surfaces touching the glue with inorganic acids. Exotic woods, some of which are diflicult to glue, such for instance as teak wood, and must ordinarily be prepared before gluing, may be glued without any preporation to any other wood with the new adhesive, which does not penetrate porous.ve-

users such as oak.

The liquid glue used for making the new adhesive may be prepared by any of the processes, the easier way howeveris to soak s'o 'd glue in diluted acids until it is entirely dissolved and then beat it on a water bath until the right consistency is obtained. The excess acid may be neutralized by meansof-alka'lis, such as ammonia or organic bases such as p ridine or its cheaper higher homologues ca led yridine oil, anilin or its homologues. If p osphoric, hydrobromic, h droch oric sulphuric, boric or oxalic aci the salts of which are used as fireproofing materials, are employed as solvents and neutralized afterwards with an inorganic base such as an alkali including ammo'a, an earth alkali, aluminum hydroxide, ziiic oxide, and

bases like amines, p ridine, sugars.

and the time of heating depend on the qualit of the glue and the mostfavorable conditions must be ascertained by experiments. A good hide glue will be liquefied by using about 2 parts of water to one part of glue and heating it under pressure and while stirring to a temperature of about 130 C. during 2 A3 hours. If eitherthe temperature or the time limits are materially exceeded the hydrolysis of the glue will go too far and a great loss of the adhesive ower may be incurred. What is obtained is a mixture of unconverted glutin and a h drolyzed substance which does not jelly an prevents the jellying of the glutin. This may be proved by adding to the liquid glue, which w1th a view to clarity I shall hereafter designate hydrolyzed glue, an excess of alcohol which will precipitate the glutin, whereasthe hydrolyzed product remains .in solution and may be recovered by evaporating off the solvent. What remains is a sticky viscous liquid which will not solidify. Such a test will show that hydrolyzed glue contains a protein (glutin) and a c eavage product. It is this latter product which acts as the protective colloid between the -glutin ,orother proteins which I may use in m process and the condensation product. ydrolyzed glue is a material which contains protein and a protective colloid and therefore a waterproof liquid adhesive is obtained on mixing it with a condensation product. I have found that a liquid glue of greater adhesiveness, however, results if the reaction is carried out at a lower temperature without lowering the pressure. This condition I attain by adding liquids with a low boiling point such as methyl alcohol or acetone. In my extended experiments I discovered that the adhesiveness of a glue solution heated under pressure is a function of time and that the shorter the time of reaction the less the adhesiveness will be impaired. I found that the time of reaction may be curtailed by adding to the water accelerators in small-proportions not exceeding 5 percent of the water used for the hydrolysis. Such accelerators are: acid alkali salts, alkali carbonates, sul phides, hydrosulphides, borax, waterglass, soaps, ammonia, hydrogen peroxide,-oxides, hydroxides of alkalis and earth alkalis, soluble salts of aromatic sulphonic acids, orgimic nto such a solution the g ue preferably in powdered form is poured while stirring and I may add to such mixture a liquid of low boiling point.

"condensation product will form with the liq- Glues may be quickly liquefied by heating in a waterbath gluepowders with double the amount of a so utioncontaining from 10 to 20% of zinc chloride or calcium chloride. A liquefaction of glues without heating which will render them less liable to coagulate with condensation products or even proofagainst precipitation may be obtained by mixing them with oils, solution of soaps (the intended scope of the expression oils and soaps having been hereinbefore set forth), glucose, fructose, dextrin, gum arabic, starches, acetin, ammonia, pyridine or a mixture of such liquids, ammonium sulphide, aniline, toluidine, formic-, acetic-, latic-, oxalic-, citric-, tartaricand other or anic and inorganic acids, such as hydroch oric, nitric, phosphoric and sul huric acids, amylalcohol, amylacetate. trongly oxidizing acids have a tanning effect on lues and are therefore not well suited for t is purpose.

As a very economical way of producing a liquid phenolformaldehyde condensation product, I have found that hypochlorites accelerate the condensation considerably if added to the mixture of both components at the beginning of the reaction, the condensation taking place in'about 15 minutes at a temperature of about C.

When calcium hypochlorite is used the oily uid glue a very strong adhesive.

As will be obvious other ingredients may be added at the suitable stage in the manufacture of the adhesive to impart other desired characteristics thereto such as a greater or lesser degree of elasticity or quicker solidification. For example, there may be added to the liquid glue rubber latex or a factis solution.

Similarly the addition of casein or blood albumin may impart greater consistency .to the adhesive. The addition of fillers such as zinc oxide, kieselguhr, graphite, or wood dust is advisable when an adhesive of a thick nature is desired.

In some cases glue which has been precipitated by condensation roducts such as first herein referred to may e liquefied by allowing it to stand with strong acids such as acetic or phosphoric acid whereby a thick tacky liquid is obtained which may be thinned out as by means of alcohol.

The product, as experiments have shown may be used for many purposes; it may be employed for instance as an adhesive in making cardboards by mixing paper pulp with it and heating it in a steampress. Or it may serve as a cement for uniting together broken china or glass. Or it may be used as the base of plastic compounds and so forth. Though the roport-ions, conditions and additions may e varied the following examples will demonstrate how the invention may be carried into effect.

. Ewwmpl el 500 parts of 40% formaldehyde are "'11 into 1000 parts of dark cresylic acid (97%) WhlCh is slowly stirred in' a steam jacketed covered pan provided wit-h a reflux coolera' and then 20 parts of finel powdered bleachmg powder are added. he temperature is kept at about 90 C. The reaction starts at once and as a rule is com leted within 30 minutes. The stirring is t en interrupted and, the mixture allowed to stand 'for an hour, after whichtime the oily condensation product has separated from the watery liquid at the bottom of the pan. It is run, while still hot into the liqui glue which is prepared-31$ as follows: 1

24 parts of sodium bicarbonate are' dissolved in 2000 parts of water which is in a steamjacketed autoclave and while being stirred 1200 arts of ground hideglue are run 1? .85 into this so ution. The autoclave is then closed, the temperature raised to about C. and the contents at this heat continually stirred, for 2 3 hours. The contents, a sticky transparent 1i uid, are then, while still hot, pressed over y the pressure in the autoclave or run into a vat provided with a stirrer and the oily condensation product is run into the liquid glue while stirring. The ultimate product obtained after the com- 95 ponents are thoroughly mixed is a very tacky liquid. If for certain purposes such a glue of a more fluid consistency be desired, for example for s raying, the oily condensation product may diluted with a suitable solvent such as methylated spirit, methyl alcohol, amylalcohol, acetic acid, or acetone. 7

For special purposes in the manufacturing of plywood which may be exposed to steaming or boiling before being moulded, a cement prepared according to the following prescription will have all desired qualities:

Example I I ous sticky black mass is obtained which'is run 5 into the hydrolyzed glue prepared as described in connection with Example I, the tem erature of which has beenbrought down to a out 55 C. by stirring.- The mixture is well stirred for a quarter of 'an hour and then the liquid cresol-formaldehydef condensation product, is run into it. The stirring is continued for about hour 'until'a thorough' mixing has taken place and abluish gre y very tacky mass is obtained, which will'retain' its liquid homogeneousconsistency, that is tosay, without separation of the various components,

for any lengtltpf time and therefore is always ready for use; This adhesive may be toothick 13o for certain purposes and if the oily condensation product miiy be diluted with a suitable solvent such as reviously mentioned.

"' adding their solutions to the liquid-glue. An

To impart to the g ue a high degree of elasticity, india rubber or factis may be used by adhesive of greaterelasticity is also obtained inthe manner as described in the following 130 C. with 120 parts of dekalin which is dekahydronaphthalene in a closed vessel with reflux cooler and stirrer and then 210 Karts of dark cresylic acid (97%) are added. fter being thoroughly mixed 60 parts of paraformaldeh do are gradually run into this mixture. he temperature is maintained at between 120-130 C. After heating for 3 hours a very viscous, thick liquid results whiich is run, while still hot, into 600 parts of h drolyzed glue of-a temperature of about 60 and which has been prepared according to Exam le I. The mixture is then continually stirre for about half an hour. An exceedingly sticky mass is obtained. with which a very elastic gluing is obtained.

Example I V v 140 parts of Chinese wood oil factis is dissolved by boiling it at 90-91 C. for 1 hours with a mixture of 350 parts'of dark cresylic acid and 300 parts of alcoholic alkali (containing 10% of caustic soda) a closed vessel provided with reflux cooler and stirrer. While being continually stirred 300 parts of 40% formaldehyde are gradually run into the mixture which is heated for 2 hours at 85 C. There results a very viscous brown liquid which is run into 1000 parts of warm hydrol zed glue, of a temperature of about 40 (3., t e mixture being well stirred for about half an hour, when a very tacky yellow liquid is obtained.

Example V washing first with hot and then with cold water will be rendered neutral, the final washing being with cold water because it separates from the oilbetter than does hot water.

30 parts of this oilare heated with 260 parts of cresylic acid to about 80 C. and then 60 arts of paraformaldehydef are gradually addhd to the well stirred solution. After heating this mixture for about 3 hours at .yellow tacky liquid.

-in cold water over night and meltin tained. It is run into a stron 80 parts of blood albumin suc c-oug ly mixed in a mill.

tain ed'which is run into 700 parts of warm lydrol zed glue of a temperature of about 60 whi e stirring. The resulting product is a Example VI One part of soap, which, as hereinbefore mixedwith parts of oily condensation product such as prepared according to Example I until the mixture is emulsified. The emulsion is run into parts of a hot glue solution (which is obtained by soakin .glue the jelly on a water bath at about 60 0.), and ground in a wet grinding mill such as is used for grinding wet paints, to a homogeneous mass of the consistency of treacle which may be thinned out with hot water. The mixing may be effected, if preferred, between di-fi'erential' rolls or masticators, or in colloidal mills.

Example VII Onepart of oily condensation product prepared according to Example I is-well mixed with-one art of hydrolyzed glue of about C. and the homogeneous mixture added to, one partof hot glue solution prepared according to- Example VI while being well stirred. A transparent very tacky liquid results which is diluted with a tenth of its weight of acetic acid, while heating the mixture to about C. in order to obtain a liquid adhesive which will spread easily.

Example VII concentrated solutionof blood albumin such I as described in Example II. The mass is well mixed in a suitable mill and thus a homogeneous semi-liquid adhesive results.

Example I X A solution of 30 parts ofgum arabic in 30 parts of water is well stirred with 30 parts of liquid cresol-formaldehyde condensation product whereby a very tacky liquid is obsolution of as may be pre ared according to Exam le II and thorhere results a thick, exceedingly sticky paste which may be thinned out with water.

The liquid cements obtained from liquid .cresol-formaldehyde condensation products and proteids or proteoids by means of protective colloids or emulsions when heated and thereby furabove 110C. will solidify nish a ver efi'ective gluing. It is obvious that other ingredients may be added to make these cements suited for the purpose for which they are to be used.

What I claim is:

1. An adhesive compound comprisin a mixture containing a liquid resinous cominsation product of an aromatic oxy-compound with an aldehyde, a rotein containing aqueous solution and su cient of a protective colloid to'inaintain the proteins dissolved.

2. An adhesive compound comprising a liquid resinous condensation product of an aromatic oxy-compound with formaldehyde, dissolved blood albumen and suflicient of a protective colloid to prevent precipitation of the albumen.

3. An' adhesive compound comprising a protein containing aqueous solution, a liquid resinous condensation product of cresylic acid with formaldehyde and suflicient of a protective colloid to the proteins.

4. An adhesive compound comprising a liquid resinous condensation product of an aromatic oxy-compound with formaldehyde condensed by means of a hypochlorite, a protein containing material and suflicient of a protective colloid to prevent precipitation of the proteins.

5. An adhesive compound comprising a liquid resinous condensation product of cresylic acid and formaldehyde condensed by means of bleaching powder, dissolved protein material, and sufficient of a protective colloid to prevent precipitation of the proteins.

6. A process of preparing a waterproof adhesive com ound which comprises condensing cresy ic acid with. about half its weight of a 40% formaldehyde solution by means of bleaching powder which is added only in small pro ortions not exceeding 5% of the weight of the cresylic acid, separating the oily condensation product fromthe aqueous layer, mixing itwith about three times it weight of hydrolyzed glue and about double its weight of a blood albumin solution.

7 A process of making a waterproof adhesive compound which comprises d1SS0lV 1I1g blood albumen in a solution of carbam de, the weight of the-carbamide notexceedin 10% of the blood albumen, adding the blo albumen solution to about two-thirds of its weight of hydrolyzedglue and mixing the resultant mass with about one-fifth of its weight of a condensation product of cresyhc acid with formaldehyde.

prevent precipitation of 8. A process of making a water roof adhesive compound which comprises olving glue in about 1% times its wei ht of a 2% aqueous solution of sodium bicaiionate in an autoclave, heating the mixture during 2-4 hours to about 120 0., mixing the cooled resultant material with about 1 times its weight of a blood albumin solution and half its weight of a liquid condensation product of cresylic acid and formaldehyde condensed by means of a hypochlorite.

9. An adhesive compound comprising a homogeneous mixture containing a liquid resinous condensation product of an aromatic oxy-compound with an aldehyde, and hydrolyzed protein, the protein being hydrolyzed to such an extent and present in such an amount that the mixture remains homogeneous. 

